4 files changed, 45 insertions, 18 deletions
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index 4bb50f75791..550f672ed4c 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -1129,9 +1129,36 @@ pub struct IdMap {
     map: FxHashMap<String, usize>,
 }
 
+fn init_id_map() -> FxHashMap<String, usize> {
+    let mut map = FxHashMap::default();
+    // This is the list of IDs used by rustdoc templates.
+    map.insert("mainThemeStyle".to_owned(), 1);
+    map.insert("themeStyle".to_owned(), 1);
+    map.insert("theme-picker".to_owned(), 1);
+    map.insert("theme-choices".to_owned(), 1);
+    map.insert("settings-menu".to_owned(), 1);
+    map.insert("main".to_owned(), 1);
+    map.insert("search".to_owned(), 1);
+    map.insert("crate-search".to_owned(), 1);
+    map.insert("render-detail".to_owned(), 1);
+    map.insert("toggle-all-docs".to_owned(), 1);
+    map.insert("all-types".to_owned(), 1);
+    // This is the list of IDs used by rustdoc sections.
+    map.insert("fields".to_owned(), 1);
+    map.insert("variants".to_owned(), 1);
+    map.insert("implementors-list".to_owned(), 1);
+    map.insert("synthetic-implementors-list".to_owned(), 1);
+    map.insert("implementations".to_owned(), 1);
+    map.insert("trait-implementations".to_owned(), 1);
+    map.insert("synthetic-implementations".to_owned(), 1);
+    map.insert("blanket-implementations".to_owned(), 1);
+    map.insert("deref-methods".to_owned(), 1);
+    map
+}
+
 impl IdMap {
     pub fn new() -> Self {
-        IdMap::default()
+        IdMap { map: init_id_map() }
     }
 
     pub fn populate<I: IntoIterator<Item = String>>(&mut self, ids: I) {
@@ -1141,7 +1168,7 @@ impl IdMap {
     }
 
     pub fn reset(&mut self) {
-        self.map = FxHashMap::default();
+        self.map = init_id_map();
     }
 
     pub fn derive(&mut self, candidate: String) -> String {
diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/html/markdown/tests.rs
index c871587a0a9..bf0451a1d9d 100644
--- a/src/librustdoc/html/markdown/tests.rs
+++ b/src/librustdoc/html/markdown/tests.rs
@@ -29,8 +29,8 @@ fn test_unique_id() {
         "examples-2",
         "method.into_iter-1",
         "foo-1",
-        "main",
-        "search",
+        "main-1",
+        "search-1",
         "methods",
         "examples-3",
         "method.into_iter-2",
@@ -191,8 +191,8 @@ fn test_header_ids_multiple_blocks() {
     t(
         &mut map,
         "# Main",
-        "<h1 id=\"main\" class=\"section-header\">\
-        <a href=\"#main\">Main</a></h1>",
+        "<h1 id=\"main-1\" class=\"section-header\">\
+        <a href=\"#main-1\">Main</a></h1>",
     );
     t(
         &mut map,
diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs
index 387ef03f067..666e59b9a04 100644
--- a/src/librustdoc/html/render.rs
+++ b/src/librustdoc/html/render.rs
@@ -3413,8 +3413,8 @@ fn render_assoc_items(
                 write!(
                     w,
                     "\
-                    <h2 id='methods' class='small-section-header'>\
-                      Methods<a href='#methods' class='anchor'></a>\
+                    <h2 id='implementations' class='small-section-header'>\
+                      Implementations<a href='#implementations' class='anchor'></a>\
                     </h2>\
                 "
                 );
@@ -3475,10 +3475,10 @@ fn render_assoc_items(
             write!(
                 w,
                 "\
-                <h2 id='implementations' class='small-section-header'>\
-                  Trait Implementations<a href='#implementations' class='anchor'></a>\
+                <h2 id='trait-implementations' class='small-section-header'>\
+                  Trait Implementations<a href='#trait-implementations' class='anchor'></a>\
                 </h2>\
-                <div id='implementations-list'>{}</div>",
+                <div id='trait-implementations-list'>{}</div>",
                 impls
             );
         }
@@ -4097,8 +4097,8 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
             ret.sort();
             if !ret.is_empty() {
                 out.push_str(&format!(
-                    "<a class=\"sidebar-title\" href=\"#methods\">Methods\
-                                       </a><div class=\"sidebar-links\">{}</div>",
+                    "<a class=\"sidebar-title\" href=\"#implementations\">Methods</a>\
+                     <div class=\"sidebar-links\">{}</div>",
                     ret.join("")
                 ));
             }
@@ -4191,8 +4191,8 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
 
             if !concrete_format.is_empty() {
                 out.push_str(
-                    "<a class=\"sidebar-title\" href=\"#implementations\">\
-                              Trait Implementations</a>",
+                    "<a class=\"sidebar-title\" href=\"#trait-implementations\">\
+                        Trait Implementations</a>",
                 );
                 out.push_str(&format!("<div class=\"sidebar-links\">{}</div>", concrete_format));
             }
@@ -4200,7 +4200,7 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
             if !synthetic_format.is_empty() {
                 out.push_str(
                     "<a class=\"sidebar-title\" href=\"#synthetic-implementations\">\
-                              Auto Trait Implementations</a>",
+                        Auto Trait Implementations</a>",
                 );
                 out.push_str(&format!("<div class=\"sidebar-links\">{}</div>", synthetic_format));
             }
@@ -4208,7 +4208,7 @@ fn sidebar_assoc_items(it: &clean::Item) -> String {
             if !blanket_format.is_empty() {
                 out.push_str(
                     "<a class=\"sidebar-title\" href=\"#blanket-implementations\">\
-                              Blanket Implementations</a>",
+                        Blanket Implementations</a>",
                 );
                 out.push_str(&format!("<div class=\"sidebar-links\">{}</div>", blanket_format));
             }
diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index 3f12fb893a4..a023d5a2d95 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -2180,7 +2180,7 @@ function getSearchElement() {
         if (collapse) {
             toggleAllDocs(pageId, true);
         } else if (getCurrentValue("rustdoc-auto-hide-trait-implementations") !== "false") {
-            var impl_list = document.getElementById("implementations-list");
+            var impl_list = document.getElementById("trait-implementations-list");
 
             if (impl_list !== null) {
                 onEachLazy(impl_list.getElementsByClassName("collapse-toggle"), function(e) {